Nerdulator> put something in

Recognised as Number

1,388

  • Positive
  • Even
  • Composite
  • 4 digits

1,388 is an even 4-digit integer and a composite number. It has 6 divisors and a digital root of 2.

Number properties

ParityEvendivisible by 2
SignPositive
PrimalityComposite
Absolute value1,388
Digit count4
Digit sum20
Digit product192
Multiplicative persistence3times the digit product can be taken before one digit is left
Digital root2repeated digit sum
PalindromicNoreads differently backwards
Happy numberNosquared-digit sums reach 1
Harshad numberNodivisible by its own digit sum

Factors & divisors

Prime factorisation2^2 × 347
Distinct prime factors22, 347
Number of divisors6
Sum of divisors σ(n)2,436
Aliquot sum1,048sum of the proper divisors
ClassificationDeficientthe aliquot sum is less than the number
Euler's totient φ(n)692integers below n that share no factor with it
Carmichael function λ(n)346the smallest exponent with aˣ ≡ 1 for every unit; smaller than φ(n) = 692
Möbius function μ(n)0zero, because a prime divides n twice
SquarefreeNohas a repeated prime factor
All divisors1, 2, 4, 347, 694, 1,3886 in total

Arithmetic

Previous number1,387
Next number1,389
Double2,776
Half694
Square1,926,544
Cube2,674,043,072
Square root37.25587202≈irrational, shown to 9 decimal places
Cube root11.154835121≈
Negation-1,388
Reciprocal0.0007204611≈

Representations

Decimal1,388
Binary1010110110011 bits
Octal2554
Hexadecimal56C
Base 3612K
Roman numeralMCCCLXXXVIII
In wordsone thousand, three hundred and eighty-eight
Ordinalone thousand, three hundred and eighty-eighth
Scientific notation1.388 × 10^3
Engineering notation1.388 × 10^3

In other bases

Ternary1220102base 3; the most digit-efficient integer base after e: 7 digits
Quinary21023base 5; one hand: 5 digits
Septenary4022base 7: 4 digits
Nonary1812base 9; each digit is two ternary digits: 4 digits
Duodecimal978base 12; divides by 2, 3, 4 and 6, which is why eggs and inches come in twelves: 3 digits
Vigesimal398base 20; hands and feet, and the Mayan and Yoruba systems: 3 digits
Sexagesimal23:8base 60; Babylonian, and still how an hour and a circle are divided: 2 digits
Balanced ternary1T0T011Tdigits −1, 0 and +1 written T, 0 and 1; negation is swapping T and 1, so no sign is needed
Negabinary1101010111100base −2; place values alternate 1, −2, 4, −8, so every integer has exactly one form without a sign

Bit-level

0000010101101100
Bit length11 bitsto write the magnitude
Set bits6the population count, or Hamming weight
Zero bits5within that length
Bit parityeven6 set bits, so even; not the same as the number itself being even
Highest set bitbit 10worth 1,024
Lowest set bitbit 22 trailing zeros
Power of twoNo
Bytes205 6c
Gray code11111011010n XOR (n >> 1); successive values differ in exactly one bit

At each machine width

16-bit0000010101101100
32-bit00000000000000000000010101101100
64-bit0000000000000000000000000000000000000000000000000000010101101100
One's complement1111101010010011at 16 bits, every bit flipped
Bits reversed0011011010100000at 16 bits
Rotated left by 10000101011011000at 16 bits, wrapping
Shifted left by 1101011011000= 2,776, no wrap
Shifted right by 11010110110= 694, discarding the low bit
These bits as a double6.85763116 × 10^-321≈IEEE-754 binary64 reinterpretation of the same 64 bits (subnormal)

Nearest landmarks

Next prime1,399+11
Previous prime1,381−7
Distance to nearest prime7
Nearest square below1,369
Nearest square above1,444

Powers & multiples

1,388 to the power 21,926,544
1,388 to the power 32,674,043,072
1,388 to the power 43,711,571,783,936
1,388 to the power 55,151,661,636,103,168
First ten multiples1,388, 2,776, 4,164, 5,552, 6,940, 8,328, 9,716, 11,104, 12,492, 13,880
Powers of twoBetween 2^10 (1,024) and 2^11 (2,048)

Divisibility tests

Divisible by 2Yes
Divisible by 3No, remainder 2
Divisible by 4Yes
Divisible by 5No, remainder 3
Divisible by 6No, remainder 2
Divisible by 7No, remainder 2
Divisible by 8No, remainder 4
Divisible by 9No, remainder 2
Divisible by 10No, remainder 8
Divisible by 11No, remainder 2
Divisible by 12No, remainder 8
Divisible by 100No, remainder 88

Collatz (3n + 1) trajectory

Steps to reach 1127the total stopping time
Highest value reached9,2326× the starting value
Reaches 1Yesthe Collatz conjecture says every positive integer does, but it is unproven
First steps1,388 → 694 → 347 → 1,042 → 521 → 1,564 → 782 → 391 → 1,174 → 587 → …
Last steps… → 5 → 16 → 8 → 4 → 2 → 1

As a percentage & fraction

As a percentage138,800%
1,388% as a decimal13.88
1,388% of 1001,388
1,388% of 1,00013,880
As a fraction of 1001,388/100

Read another way

As seconds23 minutes and 8 seconds
As bytes1.355 KiB
As a year1388 AD
As a 24-bit colour#00056C

Keep nerding

Every link below is a page Nerdulator can generate from what it already knows about this value.

Neighbouring numbers

Nearby primes

Also reads as

1388 (year)

  • Leap year
  • 366 days
  • 14th century
  • Dragon

1388 was a leap year of 366 days. It began on a Tuesday and ended on a Wednesday. Easter Sunday fell on 6 April.

Open this reading on its own page →

Structure of the year

Leap yearYesdivisible by 4, and by 400 if divisible by 100
Days in the year366
Days in February29
1 January fell on aTuesday
31 December fell on aWednesday
Century14th century
Decade1380s
Chinese zodiacDragon
Easter Sunday6 April

Patterns forced by the calendar

Weekday counts52 of each, plus an extra Tuesday and Wednesday366 days is 52 weeks and 2 days, and the remainder starts on the weekday 1 January falls on
Sundays52
Mondays52
Tuesdays53one of the extras
Wednesdays53one of the extras
Thursdays52
Fridays52
Saturdays52
Friday the 13th1 of them13 June
ISO weeks52an ordinary 52-week year
Same calendar as1360the most recent year whose calendar is identical, so a printed one could be reused
Calendar repeats in1428, 1456, 148440 years later, then again after that; the gap is 6, 11 or 28 years, broken by centuries that skip a leap year

Months of 1388

January31 days, starts Tuesday
February29 days, starts Friday
March31 days, starts Saturday
April30 days, starts Tuesday
May31 days, starts Thursday
June30 days, starts Sunday
July31 days, starts Tuesday
August31 days, starts Friday
September30 days, starts Monday
October31 days, starts Wednesday
November30 days, starts Saturday
December31 days, starts Monday

Time references

These values depend on today’s date and change daily.

Unix timestamp at the start-18,366,134,400
Unix timestamp at the end-18,334,512,001
Years from now638 years ago
Days from today233,283 days since 1 January

The number 1388

As a number1,388
In wordsone thousand, three hundred and eighty-eight
Roman numeralsMCCCLXXXVIII

Keep nerding

Every link below is a page Nerdulator can generate from what it already knows about this value.

Neighbouring years

Also reads as

#113388 (colour)

  • #113388
  • Blue
  • Dark
  • Nearest: Dark slateblue

#113388 is a blue with RGB values 17, 51, 136 and HSL 223°, 78%, 30%. It is a dark colour, so white text on it reaches 11.3:1 contrast (AAA for normal text). The nearest named colour is Dark slateblue.

Open this reading on its own page →

Colour values

#113388#113388
HEX#113388
HEX (short)#138
RGBrgb(17, 51, 136)
RGB (0–1)0.0667, 0.2, 0.5333
RGB percentages6.7%, 20%, 53.3%
HSLhsl(222.9, 77.8%, 30%)
HSV / HSBhsv(222.9, 87.5%, 53.3%)
CMYK87.5%, 62.5%, 0%, 46.7%≈naive device-independent conversion; real print needs an ICC profile
24-bit integer1,127,304
CSS custom property--colour: #113388;

Brightness & contrast

Relative luminance0.04264WCAG 2.x, 0 is black and 1 is white
Perceived brightness61 of 255ITU-R BT.601 weighting
Light or darkDark
Best text colour on this backgroundWhitecontrast 11.33:1
Contrast with white11.33:1WCAG normal text: AAA
Contrast with black1.85:1WCAG normal text: Fail
Greyscale equivalent#323232
Inverted#EECC77

Colour vision & accessibility

Normal visionProtanopiaDeuteranopiaTritanopia
Protanopia#00408Bno red cones; affects about 1% of men; ΔE 10.5 from the original
Deuteranopia#003586no green cones; the most common form, about 1% of men; ΔE 3.5 from the original
Tritanopia#004958no blue cones; rare, and affects men and women equally; ΔE 51.5 from the original
Distinguishable without hueShifts in lightness toonever rely on hue alone to carry meaning
Contrast with white, large text11.33:1WCAG large text: AAA
Contrast with black, large text1.85:1WCAG large text: Fail

Named colours

Dark slateblue · ΔE 11.1Midnight blue · ΔE 12.5Rebecca purple · ΔE 22Slate blue · ΔE 25.7Royal blue · ΔE 27.7Indigo · ΔE 29.3
Nearest named CSS colourDark slateblue (#483D8B)ΔE 11.09, a distinctly different colour
Hue familyblue
CSS keyword usableNo exact keyword

Colour harmonies

base+30°+90°+120°+180°+210°+240°+270°+330°
Complementary#886611
Analogous#116E88, #2B1188
Triadic#881133, #338811
Split complementary#882B11, #6E8811
Tetradic#88116E, #886611, #11882B

Tints, shades & saturation

+40%+30%+20%+10%base-10%-20%-30%-40%
Lighter +40%#7799EE
Lighter +30%#4A77E8
Lighter +20%#1C55E3
Lighter +10%#1744B5
Darker −10%#0B225B
Darker −20%#06112D
Darker −30%#000000
Darker −40%#000000
More saturated +25%#002C99
Less saturated −25%#243B75

Channel breakdown

R17
G51
B136
Red17 (6.7%)
Green51 (20%)
Blue136 (53.3%)
Hue222.86°
Saturation (HSL)77.78%
Lightness30%
Dominant channelBlue
Hex per channelR 11 · G 33 · B 88

Keep nerding

Every link below is a page Nerdulator can generate from what it already knows about this value.

Nerdulate something else

Nothing in mind? Surprise me · today’s page

Every value on this page was computed from “1388” by Nerdulator’s number engine. Nothing here was retrieved from a database of answers or written by a model.